<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>Document</title>
</head>
<body>
  <div id="app">
    <!-- <ul>
      <li v-for="(item, index) of msg.split('').join('')" :key="index">
        {{ item }}
      </li>
    </ul> -->
    <ul>
      <li v-for="(item, index) of msg" :key="index">
        {{ item }}
      </li>
    </ul>
  </div>
</body>
<script src="vue.js"></script>
<script>
  new Vue({
    el: '#app',
    data: {
      msg: 'hello message'
    }
  })
</script>
</html>